<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
	</body>
	<script type="text/javascript">
		var obj={
			name:"snw",
			age:18,
			sex:"man"
		}
		Object.seal(obj);
		
		obj.age=20;
		console.log(obj.age)
		
		
		Object.defineProperty(obj,"age",{
			configurable:true
		})
		
		
		
	</script>
</html>
